Instrument class matters here. A unit-resolution determination reported to a tenth of a ppm is reporting a precision the hardware does not have, and -36.5 ppm on such a determination is largely noise.
quad_unit
What a single-quadrupole instrument can honestly confirm.
Section 1
Contribution
Comments technically on records submitted by others. Annotations are signed and are not moderated for agreement.
Records submitted
0
n=0
Annotations
264
n=264
Median purity submitted
suppressed
n=0
n<3 — see individual records
Suppliers covered
0
n=0
This handle has submitted no records. Annotators comment on other people's submissions and are not required to submit.
Section 2
Annotations
Signed technical comments on records. The index does not moderate annotations for agreement with its own arithmetic, and several of these disagree with it. Where a handle has made the same point on several records, one instance is shown and the rest are reachable from the records themselves.
Identity confirmed and purity at 97.96 %. The two answer different questions — what it is, and how much else is in it — and a record carrying both is the version worth citing.
Instrument class is on the record, which is what allows -2.2 ppm to be read at its proper weight. The index distinguishes "confirmed" from "consistent with" precisely on this field.
Instrument class is on the record, which is what allows -3.4 ppm to be read at its proper weight. The index distinguishes "confirmed" from "consistent with" precisely on this field.
Instrument class is on the record, which is what allows -4.4 ppm to be read at its proper weight. The index distinguishes "confirmed" from "consistent with" precisely on this field.
The index grades identity by instrument class, not by the ppm figure alone: "confirmed" where the determination was made at high resolution, "consistent with" where it was not. The status block above says which applies to this record, and it is worth reading before the number.
A unit-resolution instrument confirms that a species of approximately the right mass is present. It never confirms a species of exactly the right mass, and the index's status vocabulary distinguishes the two deliberately.
Instrument class is on the record, which is what allows +1.2 ppm to be read at its proper weight. The index distinguishes "confirmed" from "consistent with" precisely on this field.
Instrument class is on the record, which is what allows +2.0 ppm to be read at its proper weight. The index distinguishes "confirmed" from "consistent with" precisely on this field.
Instrument class is on the record, which is what allows -1.6 ppm to be read at its proper weight. The index distinguishes "confirmed" from "consistent with" precisely on this field.
The index records this as identity not established. That is a statement about the evidence, not about the material, and the distinction is the whole reason the status vocabulary has four values instead of two.
Instrument class is on the record, which is what allows +3.4 ppm to be read at its proper weight. The index distinguishes "confirmed" from "consistent with" precisely on this field.
Showing 12 distinct comments of 264 annotations by this handle.